keith foster

The deputy police chief of Fresno, California, was arrested on Thursday and charged with multiple conspiracies to distribute heroin, oxycodone and marijuana, according to the Federal Bureau of Investigation.

Keith Foster, 51, was arrested along with three other Fresno residents, according to a statement from the FBI, reports Eric M. Johnson at Reuters.

Foster had always appeared just behind the police chief at press conferences.

"It is important that we do everything we can to maintain and enhance the trust that our citizens have in us," Fresno Police Chief Jerry Dyer said in a "he must be kidding" kind of statement at a news conference after Deputy Chief Foster's arrest. "When things of this nature happen, it does serve to erode that trust," the Chief admitted.

"This is a very sad day for the Fresno Police Department, the citizens of Fresno, and the law enforcement profession," Chief Dyer said, report Rick Montanez, Corin Hoggard and Sontaya Rose at ABC 30.

Dyer claimed he was "just made aware" of the case" after Foster was arrested n Thursday. Federal investigators were authorized to use wiretaps on telephones.